Researchers studied how undisturbed Q3 loess collapses under suction control using a special test. They did 15 tests using a CT-triaxial apparatus and analyzed the loess's structure with computerized tomography. The results showed that collapsible deformation increases as net confining pressure increases. The relationship between water content and CT data is linear until saturation. High net confining pressure leads to big volumetric strain in the loess.